Module org.eclipse.persistence.core

Package org.eclipse.persistence.internal.expressions

Class ConstantExpression

java.lang.Object

org.eclipse.persistence.expressions.Expression

org.eclipse.persistence.internal.expressions.ConstantExpression

All Implemented Interfaces:

Serializable, Cloneable

Direct Known Subclasses:

CollectionExpression, DateConstantExpression

public class ConstantExpression
extends Expression

Used for wrapping constant values.

See Also:

• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
protected Boolean	canBind
protected Expression	localBase
protected Object	value

Fields inherited from class org.eclipse.persistence.expressions.Expression

currentAlias, hashCode, lastTable, selectIfOrderedBy, shouldUseUpperCaseForIgnoreCase

Constructor Summary

Constructors

Constructor	Description
ConstantExpression()
ConstantExpression(Object newValue, Expression baseExpression)

Method Summary

Modifier and Type	Method	Description
Boolean	canBind()	INTERNAL: true indicates this expression can bind parameters false indicates this expression cannot bind parameters Defaults to null to indicate no specific preference
int	computeHashCode()	INTERNAL: Compute a consistent hash-code for the expression.
String	descriptionOfNodeType()	INTERNAL: Used for debug printing.
boolean	equals(Object object)	INTERNAL: Return if the expression is equal to the other.
ExpressionBuilder	getBuilder()	Return the expression builder which is the ultimate base of this expression, or null if there isn't one (shouldn't happen if we start from a root)
Expression	getLocalBase()
Object	getValue()
boolean	isConstantExpression()	INTERNAL:
boolean	isValueExpression()	INTERNAL:
Expression	normalize(ExpressionNormalizer normalizer)	INTERNAL: Normalize collection of values if they are expressions.
protected void	postCopyIn(Map alreadyDone)	INTERNAL: Used for cloning.
void	printJava(ExpressionJavaPrinter printer)	INTERNAL: Print java for project class generation
void	printSQL(ExpressionSQLPrinter printer)	INTERNAL: Print SQL onto the stream, using the ExpressionPrinter for context
Expression	rebuildOn(Expression newBase)	INTERNAL: This expression is built on a different base than the one we want.
void	resetPlaceHolderBuilder(ExpressionBuilder queryBuilder)	INTERNAL: Search the tree for any expressions (like SubSelectExpressions) that have been built using a builder that is not attached to the query.
void	setCanBind(Boolean canBind)	INTERNAL: Set to true if this expression can bind parameters Set to false if this expression cannot bind parameters Set to null to indicate no specific preference
void	setLocalBase(Expression e)	INTERNAL: Set the local base expression, ie the one on the other side of the operator Most types will ignore this, since they don't need it.
void	setValue(Object value)
Expression	twistedForBaseAndContext(Expression newBase, Expression context, Expression oldBase)	INTERNAL: Rebuild myself against the base, with the values of parameters supplied by the context expression.
Object	valueFromObject(Object object, AbstractSession session, AbstractRecord translationRow, int valueHolderPolicy, boolean isObjectUnregistered)	INTERNAL: Return the value for in memory comparison.
void	writeDescriptionOn(BufferedWriter writer)	INTERNAL: Used to print a debug form of the expression tree.
void	writeFields(ExpressionSQLPrinter printer, List<DatabaseField> newFields, SQLSelectStatement statement)	INTERNAL: Append the constant value into the printer

Methods inherited from class org.eclipse.persistence.expressions.Expression

addDate, addDate, addMonths, addMonths, alias, aliasForTable, all, all, all, all, all, all, all, all, all, all, all, all, allOf, and, any, any, any, any, any, any, any, any, any, any, any, any, anyOf, anyOf, anyOfAllowingNone, anyOfAllowingNone, as, ascending, asciiValue, asOf, assignAlias, assignTableAliasesStartingAt, average, between, between, between, between, between, between, between, between, between, caseConditionStatement, caseConditionStatement, caseStatement, caseStatement, cast, clone, cloneUsing, coalesce, coalesce, concat, containsAllKeyWords, containsAnyKeyWords, containsSubstring, containsSubstring, containsSubstringIgnoringCase, containsSubstringIgnoringCase, convertNodeToUseOuterJoin, convertToUseOuterJoin, copiedVersionFrom, count, create, create, createWithBaseLast, currentDate, currentDateDate, currentTime, currentTimeStamp, dateDifference, dateDifference, dateName, datePart, dateToString, decode, descending, difference, distinct, doesConform, doesConform, equal, equal, equal, equal, equal, equal, equal, equal, equal, equal, equalOuterJoin, equalOuterJoin, equalsIgnoreCase, equalsIgnoreCase, except, except, exceptAll, exceptAll, exists, existsNode, extract, extractFields, extractPrimaryKeyValues, extractValue, extractValues, extractXml, from, fromConstant, fromLiteral, get, get, getAlias, getAllowingNull, getAsOfClause, getAsOfClauseRecursively, getClonedField, getField, getField, getFields, getFieldValue, getFunction, getFunction, getFunction, getFunction, getFunctionWithArguments, getLeafDescriptor, getLeafMapping, getName, getNumberVal, getOperator, getOperator, getOwnedTables, getParameter, getParameter, getParameter, getProperty, getSelectionFields, getSelectionFields, getSession, getStringVal, getTable, getTable, getTableAliases, greaterThan, greaterThan, greaterThan, greaterThan, greaterThan, greaterThan, greaterThan, greaterThan, greaterThan, greaterThan, greaterThanEqual, greaterThanEqual, greaterThanEqual, greaterThanEqual, greaterThanEqual, greaterThanEqual, greaterThanEqual, greaterThanEqual, greaterThanEqual, greaterThanEqual, hasAsOfClause, hasBeenAliased, hashCode, hexToRaw, ifNull, in, in, in, in, in, in, in, in, in, in, in, in, index, indexOf, intersect, intersect, intersectAll, intersectAll, isClassTypeExpression, isCompoundExpression, isDataExpression, isEmpty, isExpressionBuilder, isFieldExpression, isFragment, isFunctionExpression, isLiteralExpression, isLogicalExpression, isMapEntryExpression, isNull, isObjectExpression, isParameterExpression, isQueryKeyExpression, isRelationExpression, isSubSelectExpression, isTableExpression, isTreatExpression, iterateOn, join, lastDay, leftJoin, leftPad, leftPad, leftTrim, leftTrim, length, lessThan, lessThan, lessThan, lessThan, lessThan, lessThan, lessThan, lessThan, lessThan, lessThan, lessThanEqual, lessThanEqual, lessThanEqual, lessThanEqual, lessThanEqual, lessThanEqual, lessThanEqual, lessThanEqual, lessThanEqual, lessThanEqual, like, like, like, like, likeIgnoreCase, likeIgnoreCase, literal, localDate, localDateTime, localTime, locate, locate, locate, mapEntry, mapKey, maximum, minimum, monthsBetween, newTime, nextDay, noneOf, not, notBetween, notBetween, notBetween, notBetween, notBetween, notBetween, notBetween, notBetween, notBetween, notEmpty, notEqual, notEqual, notEqual, notEqual, notEqual, notEqual, notEqual, notEqual, notEqual, notEqual, notExists, notIn, notIn, notIn, notIn, notIn, notIn, notIn, notIn, notIn, notIn, notIn, notIn, notLike, notLike, notLike, notLike, notNull, nullIf, nullsFirst, nullsLast, operator, or, performOperator, postfixSQL, prefixSQL, ref, regexp, regexp, registerIn, replace, replicate, replicate, resetCache, reverse, right, right, rightPad, rightPad, rightTrim, rightTrim, roundDate, selectIfOrderedBy, setSelectIfOrderedBy, shallowClone, size, size, some, some, some, some, some, some, some, some, some, some, some, some, sql, standardDeviation, subQuery, substring, substring, substring, substring, sum, toChar, toChar, toCharacter, toDate, toLowerCase, toNumber, toString, toString, toUpperCase, toUppercaseCasedWords, translate, treat, trim, trim, truncateDate, twist, type, union, union, unionAll, unionAll, validateNode, value, value, value, value, value, value, value, value, value, value, valueFromObject, variance, writeAlias, writeField, writeSubexpressionsTo

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Field Details

value

protected Object value

localBase

protected Expression localBase

canBind

protected Boolean canBind

Constructor Details

ConstantExpression

public ConstantExpression()

ConstantExpression

public ConstantExpression(Object newValue,
 Expression baseExpression)

Method Details

equals

public boolean equals(Object object)

INTERNAL: Return if the expression is equal to the other. This is used to allow dynamic expression's SQL to be cached.

Overrides:

equals in class Expression

computeHashCode

public int computeHashCode()

INTERNAL: Compute a consistent hash-code for the expression. This is used to allow dynamic expression's SQL to be cached.

Overrides:

computeHashCode in class Expression

descriptionOfNodeType

public String descriptionOfNodeType()

INTERNAL: Used for debug printing.

Overrides:

descriptionOfNodeType in class Expression

getBuilder

public ExpressionBuilder getBuilder()

Return the expression builder which is the ultimate base of this expression, or null if there isn't one (shouldn't happen if we start from a root)

Specified by:

getBuilder in class Expression

getLocalBase

public Expression getLocalBase()

getValue

public Object getValue()

setValue

public void setValue(Object value)

canBind

public Boolean canBind()

INTERNAL: true indicates this expression can bind parameters false indicates this expression cannot bind parameters Defaults to null to indicate no specific preference

setCanBind

public void setCanBind(Boolean canBind)

INTERNAL: Set to true if this expression can bind parameters Set to false if this expression cannot bind parameters Set to null to indicate no specific preference

isConstantExpression

public boolean isConstantExpression()

Description copied from class: Expression

INTERNAL:

Overrides:

isConstantExpression in class Expression

isValueExpression

public boolean isValueExpression()

INTERNAL:

Overrides:

isValueExpression in class Expression

normalize

public Expression normalize(ExpressionNormalizer normalizer)

INTERNAL: Normalize collection of values if they are expressions. or collection of collection expressions.

Overrides:

normalize in class Expression

postCopyIn

protected void postCopyIn(Map alreadyDone)

INTERNAL: Used for cloning.

Overrides:

postCopyIn in class Expression

printSQL

public void printSQL(ExpressionSQLPrinter printer)

INTERNAL: Print SQL onto the stream, using the ExpressionPrinter for context

Specified by:

printSQL in class Expression

printJava

public void printJava(ExpressionJavaPrinter printer)

INTERNAL: Print java for project class generation

Overrides:

printJava in class Expression

rebuildOn

public Expression rebuildOn(Expression newBase)

INTERNAL: This expression is built on a different base than the one we want. Rebuild it and return the root of the new tree

Specified by:

rebuildOn in class Expression

See Also:

• Expression.cloneUsing(Expression newBase)

resetPlaceHolderBuilder

public void resetPlaceHolderBuilder(ExpressionBuilder queryBuilder)

INTERNAL: Search the tree for any expressions (like SubSelectExpressions) that have been built using a builder that is not attached to the query. This happens in case of an Exists call using a new ExpressionBuilder(). This builder needs to be replaced with one from the query.

Specified by:

resetPlaceHolderBuilder in class Expression

setLocalBase

public void setLocalBase(Expression e)

Description copied from class: Expression

INTERNAL: Set the local base expression, ie the one on the other side of the operator Most types will ignore this, since they don't need it.

Overrides:

setLocalBase in class Expression

twistedForBaseAndContext

public Expression twistedForBaseAndContext(Expression newBase,
 Expression context,
 Expression oldBase)

INTERNAL: Rebuild myself against the base, with the values of parameters supplied by the context expression. This is used for transforming a standalone expression (e.g. the join criteria of a mapping) into part of some larger expression. You normally would not call this directly, instead calling twist See the comment there for more details"

Overrides:

twistedForBaseAndContext in class Expression

valueFromObject

public Object valueFromObject(Object object,
 AbstractSession session,
 AbstractRecord translationRow,
 int valueHolderPolicy,
 boolean isObjectUnregistered)

INTERNAL: Return the value for in memory comparison. This is only valid for valueable expressions.

Overrides:

valueFromObject in class Expression

Parameters:

isObjectUnregistered - true if object possibly not a clone, but is being conformed against the unit of work cache.

writeDescriptionOn

public void writeDescriptionOn(BufferedWriter writer)
                        throws IOException

INTERNAL: Used to print a debug form of the expression tree.

Overrides:

writeDescriptionOn in class Expression

Throws:

IOException

writeFields

public void writeFields(ExpressionSQLPrinter printer,
 List<DatabaseField> newFields,
 SQLSelectStatement statement)

INTERNAL: Append the constant value into the printer

Overrides:

writeFields in class Expression